This invention relates to an automatic telephone dialing system for use in multiple trunk multikey Touch Tone telephone systems for accessing long distance telephone systems such as MCI or NPS while maintaining both the telephone number and the access code secret from the typical user.
The various long distance dialing services typically buy long distance time from the telephone company in large blocks at low rates then resell time to individual users at a lower rate than the telephone company. To access the service, first a typical seven digit local number is dialed to reach the service. The user then awaits a dial tone and then proceeds to dial an access code of typically five to seven digits followed by the three digit area code and the telephone number of the party to be called. A minimum of twenty two digits must be dialed. Also, the codes for the access to the long distance service must be published to those who operate the system. If the security of the code maintenance is breached, unauthorized persons may use the codes to access the long distance service.
In order to solve this problem, the telephone company has available speed dialing options. However the speed dialing option must be installed on each and every telephone in the system at a high installation cost and monthly use fee. Electronic telephone systems are also available that have a speed dialing feature but the cost of these systems far exceed the savings of a long distance dialing service.
To overcome the cost and installation problems of the current available speed dialing system, the present invention provides a novel dialing device that can be connected in parallel with any one telephone in a multiphone multitrunk touch tone installation by simply plugging it between any telephone instrument connector and the mating cable connector anywhere in the system. Then the ADS will function for all the telephones in the system. The ADS system then scans all the trunk lines in the system sequentially until a single 1477 hertz tone is detected for 300 milli-seconds without interruption which is produced by simultaneously pressing any two buttons in the right vertical column of the telephone key pad including the digit 3, 6, 9 and #. Upon detection of the proper tone, the ADS ceases scanning and locks on to the particular trunk line where the proper tone is present. Upon release of the two simultaneously held buttons, the ADS automatically dials the long distance telephone company access seven or eight digit telephone number. Upon pick up by the service, another dial tone is heard at which time the user again simultaneously presses the two proper keys on the telephone keypad. Upon release of the two simultaneously held buttons, the ADS automatically dials the access code of the long distance dialing service. The user may then dial the area code and the telephone number of the telephone being called.
Further, in accordance with the invention, the installation of the ADS can be easily installed by the user, can be easily programmed by the user, can be easily accessed by the user, provides security for the codes needed to access the long distance dialing service, is low cost, and can be retrofitted in any existing touch tone dialing system.